Seating products utilizing modular springs which extend between the front and back rails of a generally rectangular seating frame are known. Such modular springs are conventionally attached at the front end to the front rail and attached at the back end to the rear rail. Additionally, each modular spring is bowed between the front and rear rails so as to provide a desired degree of resiliency in the seating product. The ends of each modular spring are secured to the frame rails with any of a number of mechanisms, the most common being clips secured to the front and back rails of the generally rectangular frame into which the ends of the modular springs are inserted. These modular springs may either be sinuous springs such as are disclosed in U.S. Pat. Nos. 4,247,089 and 4,586,700, or irregularly shaped springs such as are disclosed in U.S. Pat. Nos. 2,856,989 and 2,934,133.
Oftentimes, due to the distance between the front and rear rails of the seating frame (the distance the modular springs must span), it is desirable to support the center of the modular springs. U.S. Pat. Nos. 4,247,089 and 4,586,700 disclose wire members which pass diagonally under bowed sinuous springs to which are attached support members midway between the front and rear rails in order to better support the arched sinuous wires extending between the front and rear rails of the seating frame.
Rather than using a wire member passing diagonally underneath the sinuous springs spanning the length of the seating product, several seating assemblies have a frame including a center support member extending generally parallel the front and rear frame rails which is secured to a pair of opposed side rails of the frame. U.S. Pat. Nos. 2,856,989 and 2,934,133 disclose such a center support rail. In each of these patents a portion of the modular springs spanning the length of the seating product, i.e., from the front rail to the rear rail, also has a downwardly extending portion which is supported by the center rail.
Another patent which discloses a frame having at least one center rail parallel the front and rear rails is U.S. Pat. No. 5,61 5,869.
This patent discloses a pair of intermediate rails parallel the front and rear rails of the frame. A plurality of modular springs extend between the front and rearmost intermediate rail rather than between the front and back rails of the frame. A plurality of conventional coil springs secured to the forwardmost intermediate rail of the frame provide additional support to the user. These coil springs extend upwardly from the forwardmost intermediate rail and are secured to a pair of lateral wires which are secured to the modular springs as well. Because the spring assembly disclosed in U.S. Pat. No. 5,615,869 utilizes both modular springs and conventional coil springs, and additionally includes two intermediate rails extending parallel the front and back rails of the frame, it is expensive and time consuming to manufacture and assembly this spring assembly.
Therefore, it has been one objective of the present invention to provide a seat assembly for use in furniture and the like which utilizes a minimum number of components and which may be quickly and easily assembled in order to make the seat assembly.
It has further been an object of the present invention to provide a seat assembly utilizing modular springs which have a resilient center section secured to an intermediate rail of a generally rectangular frame, without the rear end of the modular spring being secured to the rear rail of the frame, thereby minimizing assembly and manufacturing costs and maximizing seating comfort of the resulting product.
It has further been an object of the present invention to provide a seating assembly which may be modified slightly in order to manufacture seats of differing lengths.